Process of making tools.



J. DE BOSREDON. PROCESS OF MAKING TOOLS. V APPLIOATION FILED 001 .13, 1911.

1,025,735. Patented May 7, 1912.

m: 4. 0. f C, A, W,

JEAN DE BOSREDON, OF PARIS, FRANCE. 5

raocnss or MAkING TOOLS.

I Specification of Letters Patent,

Patented May '7, 1912 Application filed October 13, 1911. Serial No. 654,465.-

To all whom it may concern:

Be it known that I, JEAN on BOSREDON, a citizen of the French Republic, residing at Paris, France, have invented certain new and useful Improvements in Processesiof Making Tools,- of which the followingis a specification.

It is well known that in-a tool, whatever be its nature and application, there are two parts: one works in an active manner attacking the material to be machined, while the other forms merely a support for the former and enables it tobe secured or given the movement necessary for operating it. In these conditions, it is obvious that it would be of great advantage, both from the point of view of cost price and of normal working of the tool, to make the said parts in such a manner that the material utilized for making them, should satisfy, more articularly by its qualities of strength, e asticity etc. their conditions of use. Thus, a turning tool could be for instance constituted by a soft steel body, by which it would secured to the machine during the working eriod,

while the working portion would be ormed by a high speed steel tip.

It has been already attempted to make such tools either by utilizing tool holders in which removable tips of high speed steel were secured b any suitable means, or by rendering the tips integral with the portion of soft steel intended tosupport them and.

form with it one whole. 1

' The first solution has the disadvantage of necessitating special tools and moreover does not fulfil theobject desired, for in-order to produce a perfect adhesion of the tip in the jaws of the tool holder, it is necessary that the latter should have fairly large dimensions, and consequently it is impossible, for any dimensionsbelow the said. best dimensions, to utilize completely the working steel portion. Moreover, it is impossible to secure the tool and the tool holder together thoroughly, so that the tip is exposed to-vibrations affecting its work.

The second solution consists in securing the tip to a toolmade of soft steel playing the same part, as regardsits erecting on the remedy that disadvantage, the tipWas -gem nection that could resist their separation so 'way of example, Figure 1 shows parts together securely, owing to the impossibility at pres- --shape that it rests against ashoulder proordinary steel, but the'work quickly destroyed the retaining lips or flanges, and the piece of high speed steel gradually became loose. Securing by a heterogeneous welding (for instance by brazing) was also tried, but the reliability was insuflicient, as there was not between the two steel parts of differentv nature sufficiently intimate molecular 0on that the tip was broken ofl', b its own 'resistance, from the piece of so t steel which underwent different deformation. a Thecombination of these two means; setting or framing, and heterogeneous welding, has not given any better results. over, this second solution does not allow. the tool constructed in accordance with these. means, to be reforged or retempered.

1 This invention relates to a process by means of which a tip of highspeed steel can'be secured direct by autogenous welding, to a soft steel tool, so as to obtain new products characterized by the said tip forming one piece with and bein thoroughly secured to, its support, so that 1t is possible to consider these tools as being constituted in one piece, the elements of which have different properties. In that way, an industrial result is obtained which can be compared to that consisting ,for instance in tempering the working surface of a soft steel tool, with theessential difference that the said portion is constituted by a-highfspeed steel. In the accompanying drawing. given by of a turning tool and the formation of the Moree blank high speed steel tip which is to be welded to it. Fig. 2 shows the said parts super of the same tool after welding and erecting. v For carrying out the process according to posed before welding, and Fig. 3 is a view this invention,'the support a of soft steel' i j made in suchmanner as to give it'the shape face 5 which is to reoeive'the tipc-ofhigh speed steel forming the working part, is scraped out. This surface of application b is, if necessary, machined in; such manner that the corresponding contact surface. of the tip- 0, previously shaped,shou ld exactly of'an ordinary tool, and the application sur and closely fit it. As shown in the drawing,

the tip 0 is given at its rear portion such a the tip 0 of high speed steel on the support \a of soft steel, the steel of the greatest expansion is heated to about 800, andthe other part to about 900, whereupon they .are superposed, some anti-oxidizing material, for instance borax, being: placed between the surfaces in'contact.

The parts connected together, are submitted to a sufficient pressure for insuring adhesion, the said action taking place without shocks and by any suitable means, by

. arranging for instancethe whole in a die which guides the tip on the tool and keeps it 2 dur'mg the application of the pressure. This tool can be subsequently submitted to. an

first stage of treatment insures an adhesionof the two surfaces incontact, but in order to bring about areal welding, the whole is placed into a furnace where itcan be heated 25 to between 1200 and 1400 ,When the tool is raised to that temperature, it is introduced into a die which it fits exactly, and submitted to a very strong pressure exercised by any suitable means, but without shocks. In these conditions, the point or tip '0 of high speed steel, and the supporting tool a being submitted to such a pressure that there can take place no deformation or expansion (since the die prevents any shift ing of the material) ,are welded together by a kind of filtration and molecular exchange taking place between both the surfaces of contact, owing to the elevation of temperature which makes possible a movement of the molecules. In these conditions, a whole is obtained (Fig. 3) the parts of "which are ins'eparably secured together, so that the physical or thermic treatments like an OI'dlnary tool. Thus the tool vis finally shaped f speed steels.

by grinding, then the tip is tempered in petroleum or air or in any other way, or by any other suitable The tools thus obtained can be forged and tempered again, if necessary, practical experience having shown that the welding of the high speed steel tip on the soft steel tool is such that it can undergoany therlnic treatments and mechanical actions necessi:

,tated by the said various operations.

- What I claim as my invention and desire to secure by Letters Patent is 1. The process of making'tools, having a working part of high speed steel and a body of softer metal, comprising shaping the working part and body to fit closely together, preliminarily heating said part and the section of the body to which it is to be applied to temperatures which are a function of their'coeflicients of expansion, fitting the working part to the body under pressure, subsequently heating said assembled members to a temperature in excess of that of the preliminary heating and then arranging them in a matrix of suitable shape and subjecting them to pressure.

2. A process for making tools consisting in shaping a working part of high speed \steel'and a support part of soft steel to fit together, heating the part having the highest coeflicient'of expansion to about 800 and the other part to about 900, interposing an anti-oxidizing material between the parts, ,placing them together, submitting them to pressure, and subsequently heating them' to about 12001400, and again submitting them to strong pressure. I

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

JEAN on BOSREDON. Witnesses:

H. C. Coxn, Gnoncns BoNnnUIL.

process .used' for high 

